High power pedal-operated grease gun



May 12, 1931. ALBER'UNE 1,804,731

HIGH POWER PEDAL OPERATED GREASE GUN Filed Jan. '7, 1929 l E I l I 5 ATTORNEY Patented May 12, 1931 HERMAN ALBERTJNE, or nU'rHEnFoRD, NEW

`man:eonwiazn Vr14:1).111.-orrzaunfrun amsn GUN Application mea January v,- 1929. serial No. 330,803.

The'grease gunof the present invention is designed to supply'7 oil or grease to bear- `in s, gear housings,-universal joints, etc., `eit er directly or through. grease cupsfor through detachable couplers and fittings,

which are used in place of grease cups 1in accordance with force feedk lubricating sys? tems after thev mannervv described. `in the British patent to Alley, et al., 21,893 of 1906. It includes a .force feed reservoir supplying grease to va single yacting high pressure pump, somewhat as rin'nly Patents -fNosl. 1,689,186 and 1,686,309, but more. exactly as in my application. Ser.v No. 190,726, filed y May 12th, 1927, in which latter, a--small capacity, high pressure plunger is arranged in a cylinder integral-with the base which carries the reserviorthat supplies grease to the pump.k The pump is of the valveless type in 7which the pump cylinder inlet. is opened and' closedby the pump piston,jand the pump `cylinder being arranged horizontally below the supplyreservoir, grease from the latter flows directly into the pump 52.15 cylinder on the retraction stroke ofthe piston, this `piston o n its working stroke forcing the grease through a .valveless outlet, into the usual flexible conduit whence it passes to .the bearings. The plunger lis -A operatedbya down-stroke-leve'r system and the baseo the `reservoir is detachablysecured toa stable base adapted to sustain the.

operating down pressure so that it will not cause upset of the reservoir. 1 The present' invention is particularly concerned with the provision of an improved operating mechanism kfor the pump plunger, this mechanismbeing designed forutilizing a manual or pedal .pressure parallel with the 40 reservoirto ellect a slow, powerful forward thrust of the pump piston and release and automatic yrapid return stroke thereof; The mechanisml is also designed to give a substantial maximum thrust on ythe piston kat the end of its expelling stroke, when it is mostf'needed; alsoin a',directon andat a timewhen. the most powerful lateral thrust on the free end ofthe plunger will be least effective for bending or breaking it. It ini CJ cludes4 a foot operated lever. or treadle, the

range of Vmovement of Vwhich'lis relatively small and approximates lvertical so that it can be conveniently rapidly pedally depressed without .tiring the operator and without need for any special care in the manner of applying the foot pressure.y

. The-operating mechanismis of especially jrugged and durable construction, involving no movable .fulcrum and designed .to minimize bending or -twistin stresses on the pump plungery during t e high `pressure part of its forwardstroke. vN eitherV careless handling of the apparatus nor the accidental dropping of heavy articles vupon itis apt to injure the device. Such mechanism yrepresents afmaterialimprovement over the operating means shown in mynabove mentioned .pending application', wherein there is l'a compoundfmovement of. a manually o er. ated` lever arranged to swing from initial outward, horizontal movementto a final vertical movement, so that only the latter art of the movement could be accom lished y. ydownspressure of the foot. Suc part manual, part pedal operation was .more awkward and in certain. positions imposed undesirable bending stresses on thek pump piston. Moreover, the great angular swil of the lever necessitated a rfloating or li fulcrum for the lever, exposing the plunger so to direct transverse or bending stresses applied directly j downward from the lever lthroughoutits stroke..

` The device of the present invention facilif tates simple, rapid, `down pressure operau tion', requires less careful manipulation'and is in other respects better suited forthe rough and` careless handling'to which such apparatus is very aptv to be subjected in an Yordinary garage.

The invention may be more fully understood from the following description in connection with the accompanying drawings,

i wherein Fig. 1 is aperspective view of a high pow- 95 ered greasefgun embodyingthe invention;

Fig. .2 isa broken view mainly. in longitudinal section through the apparatus.

In the .drawings .the grease reservoir 10 is shown as screwed into a suitably threadloo flange ed socket 11 formed in a cast base 12. The top of the reservoir is closed by-a .screw cap 13 including anoutwardly extending portion 13a abuttn thetop of the cylin er 10 and downwar y extendin threaded portion 13b having-t ed agement with the 'cylinder kand removab y secured in place as by a `blind rivet 13e..

Mounted to-'slide in a central opening in the cap 13 is a piston rod 14 an operating handle 15 at its S,u r en and a piston at its lower end. e latter may conventionally comprise o positely directed cup leathers 16 and 17 he d .between clam i plates 18. This piston is secured to e rg 14 in any suitable manner as by forming the latter with `a shoulder 19, a re' u shank 20 which asses through the piston and a head 21 which isl riveted over to clamp the iston against the shoulder.

T e piston is normally pressed downwardly b acoiled conical'spring 22 havints sma er end centered about a pendent ss l 23 on the cap 13 and its lower end centered by an upstanding marginal ange 18a on the upper clampin plate 18.

The piston may the spring, by means ofthe handle 15, when the projecting ends of pins 24 are in re istry with slots 25 in the cap 13. After t e handle 'has been drawn upwardly a suliicient distance so that the pins 24 clear the cap, the handle may be rotated tok move the ins out of regist with the slots 25 whereby the piston wil be held in vits fullyr -retracted ition. To prevent accidental rotation oixtlie piston in this position, locking notches 26 maybe provided as seats for the ins.

p With the ins thus seated as in Fig. 2, the rod 14 is ocked to the head 13 and since the head is permanently locked to the cylinder bythe rivet 13e, the latter may be unscrewed from the base 12 by using the handle 15 as a wrench. The cylinder may then be packed with grease through its open end y and again screwed to `the base.

Integral with the base 12 is the horizontal pump cylinder 27 in which slides the plunger -rod 28 working through a stuilng box 29 at one end of the cylinder 27. The grease passes from the reservoir 10 into the vpump cylinder- 27 through an inletl port 30 iiared'y outwardly at its top and communicating with a passage 31 extending :completely around the cylinder 27l so as to permit thev supply of grease to this cylinder from all sides` as soon as the end of the piston 2.8 starts to clear the wall of the port 30 on the retraction stroke of the piston.

On the working stroke of the piston the grease which has entered the cylinder 27 is pressed forwardly through a reduced bore 32 into a flexible conduit 33 preferably of .pressure in the hose;

. becomes less im retracted, compressing -metal and adapted to sustain very high in- .ternal preures.

This conduit is lprovided with a nipple 34 screwed into the base 12 and a iitti 35 to be attached to the fitting on'the mac 'ne to be lubricated. shIn the event that thhnliiit 33 is very ort, it is important' assagewa 32 should be considerably restrildted. Thiys construction of course uires a slow forward stroke ofthe pistonk ut prevents much grease from fiowin bac on the ra id retraction stroke of t e piston and 'eving Where the conduit 33, however, is fairly lon and the grease isfairly heavyz there be such a strong frictional resistance to'return iow of grease to the pump cylinder duri the quick retraction stroke of the piston t at the size of the passage 32 rtant and in fact may in some instances' substantially as lar as the cross section of the pump cylinder itself without materially impairng the eiiiciency of the apparatus or the pressure which may be built up in the conduit 33. v

The handle `15 mayz have a bifurcated end 15a' to conveniently hold the hose-33 or the fitting1 35 on the end of the ho, so that the ose ywill'not be draugged about ther floor and stepped on when e device is not in use.

At its outerend, the pump cylinder 27 communicatesytthrou li a priming oulet or vent 36 with a.k bore 3g! into which isscrewed plug 38 having a reduced inner end terminating in a conical point which. normally fpro'ects into the upper end of the passage 36 at t e conical lower end of the bore 37. At vone side of thebore 37. therel is openi 39 (indicated in dotted lines) through which airv or lubricant forced past the conical plug 38 may be vented.

the base is removably fitted intoan antitilting secondary 'base structure which includes diver angle iron members 40 connected at their divergent ends by a crosspiece 41 and at their convergent ends substantially fitting the tapered portion of the base 12 and secured thereto by rods 42 extending through openings in the legs 12a and in the upright flanges of the angle irons 40, these rods beiv held in place in any suitable manner as y the cotter pins 43 which'are passed through openings in their ends.

The apparatus as thus far described is in many respects quite similar tothe disclosure in myv prior application above referred to, the present invention being more especially concerned with the arrangement and construction of the pedally operated mechanism vfor reciprocating the pump plunger 28.

This mechanism. includes a bell-crank lever 44 pivoted on a fixed fulcrum 45 andy having its shorter end 46 connected by link 47 to the piston rod 28. 4 This is a notable improvement' over my prior device in which necessary offset relation of the fulcrum is obtained by lioating it on the end of link. The irregularity of the bell-crank'lever 44 the lateral oilset of its fixed. fulcruml an the length of the link are so related that the working stroke ofthe piston mayv be effected by stepping on the pedal 48v at the free endof the longer ,arm 49 'of the lever. The retraction stroke of the pump pistonis automatically effected-by the coiled springs 50.

' While the fixed fulcrum 45 might, if de-` sired, be made as an integral part of the base casting 12, I have in the resent instance elected to show a rearwar ly extending ri id plate 51. This plate is fixedly secure to the casting by rivets or pins 52 o which hold the forward en d of the plate in position between a pair of upstanding ears 53 at therear end of the casting'12; The longer arm 49 and the shorter arm 46 of the lever. 44 are disposed at approximately 45 angles relatively to each other and at the elbow of the lever the latter is recessed as at 54 to accommodate the rearwardly extending end of the plate 51 and isr connected to such late end by the fulcrum pin above re erred to.

The walls of the slot v54 are operative, as will be apparent from Fig. 2 to limit movement of the lever 44 under the inluenceof foot pressure on the pedal 48 or under the iniluence of the restorlng springs 50. These s rings are anchored to the ears 53 and to t e projecting ends of a pin 55 carried by a projection 56 at the elbow of the angular lever 44. Downward movement of the lever is preferably limited by its pedal portion striking the ground or the cross bar 41 of'V the base.

Link 47 which connects arm 46 and piston 28 is relatively short and sturdy. One end of this link is pivoted as by pin 57 between the bifurcated end of the shorter arm 46 of the lever and the other end of the link is in turn bifurcated as at 58 to receive the reduced end 59 of the piston 28 which is pivoted between the furcations by pin 60.

In practice the construction may be such lthat with the piston 28 in its fully retracted 'around neede When the pedal is in this position, at the beginning of the forward stroke of piston, the link 47is at an angle of about 30 to the horizontal andnot at the mostefective ,angle for exerting a direct forward thrust on the iston 28. But, at this time and for a vconsi erable part of the initial movement of the' lever arm 49 toward the depressed position, the inlet ort permits free reverse 4ow of grease, so t at piston 29 encounters little res1stance and by the time the port is closed and the piston 2 8 meets a strongresistance, the link 47 will-have straightened out into substantial axial'l alignment with will not exert strains on the plungerl sui-l outside" cient to spring it, bendit or cause leakage it. There is' never at any stage of the movement any tendency to exert a-direct upward prying stress or transverse bending strain on the pump piston and the power for operatin the piston-is transmitted when most in a very effective manner. s It will be seen that this a paratus, particularly the operating mec anism, is of.

such rug edy and durable type and is so arou ranged t at accidentally stepping on it at the wrong place or dropping a heavy weight upon it wi l do nothing more thanl depressr thelever and force the plunger in.- Con- Vlos trary to the device of my prior application no compound 'swinging and depressin movement is necessar any force applied to t e lever 49 whichhas va downward component in it will beeiective to operate the mechanism.

' In practice the piston 28 will be about one-half an inch in diameter and 4the part 32 may be, say, one-quarter inch :'.n diameter. By rapid oscillation of the lever 49 pressures up to say 10,00() pounds per square inch or more may be built up in the conduit 33 as above described and yet but little power is required to effect the return stroke of the pump piston. This piston in its retraction stroke can only draw about three pounds of vacuum, so that the s rings 50 need not be particularly powerful? What I clalm is:

1. In a grease gun of the character which includes a base, an upright reservoir thereon, a substantially horizontal pump cylinder formedk in said'base having an intake receiving grease from the reservoir and a plunger working horizontally in the cylinfor operation s an `angle to each other and spring means normally holding the lever with its power. receiving arm disposed at approximately to the horizontal.

2. In a rease gun of the character which includes a ase, an upright reservoir thereon, a substantially horizontal pump cylinder formed in said base having an intake receiving grease from the reservoir and. a plun er working horizontally in the cyllnder, Ioot-operated ower multi lying means for actuating the p unger inclu ing an angular lever, a fulcrum for the elbow of the lever laterally offset from but fixed relatively to the base and a link shorter than the distance of said offset connecting one end of the lever to the pump plunger, spring means urging the lever to plunger-retracting'position and means limiting the plunger-retractng movement of the lever so that the upper arm thereof is normally disposed at a convenient angle to be pedally depressed.

3. In a grease gun of the character which includes a base, an upright reservoir thereon, a substantially horizontal pump cylinder formed in said base having an intake receiving grease from the reservoir and a plunger working horizontally in the cylinder, pedally operated power multiplying means for actuating the plun er including an angular lever, a ulcrum or the elbow of the lever laterally offset from but fixed relatively to the base and a link connecting one end of the lever to the pump plunger, the lever including a relatively long arm and a relatively short arm, the longer arm of the lever being disposed uppermost and carrying a pedal at lts free end and the shorter arm of the lever being connected vto the link.

4. Apparatus as set forth in claim 3 and wherein the link is relativel short and is moved into axial alignment with the plunger which it operates during the power stroke ofthe lever.

5. In a f rease gun of the character which includes a ase, an upright reservoir thereon,

.y a substantiallyl horizontal pump cylinder formed in said base having an intake receiving grease from the reservoir and a plunger stop means coactin with the walls of the recess to limit the t ow of the lever.

6. In a rease gun of the character which includes a ase, an upright reservoir thereon, a substantially horizontal pump cylinder formed in said base having an intakel receiving grease from the reservoir and a lunger working horizontally in the cylinder, pedally operated power multi lying means for actuating the plun er inclilding an angular lever,l a fulcrum or the elbow of the lever laterally offset from hutxed relatively to the base and a link connecting one end of the lever to the pump lunger, coiled contractile springs anchoredp to the base and engaging t e lever in the region of its fulcrum to normally move the latter to plunger-retracting position.

7. In a grease gun of the character which includes a base, an upright reservoir thereon, a substantiall horizontal pump cylinder formed in said ase having an intake receiving grease from the reservoir and a plunger working horizontally in the cylinder, pedally operated power multi lying means for actuating the plunger, inc uding ears on the base, a plate fixed between the ears and projecting 1n a substantially horizontal direction, an angular lever fulcrumed on the end of the plate and a link connecting one end of the lever to the pump plunger.

Signed at New York, in the county of New York and State of N ev.' York, this 5th day of January, A. D. 1929 HERMAN ALBERTINE.

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